EGR valve - 2.2dCi

[ianP]

Hi,  same here...  flat as a pancake!  Not had my car back from the garage yet so not sure if them cleaning the EGR for the second time will have helped...  forgive my for my ignorance here,  but...  what's the diffuser for (and where do I find it?)...  please don't say it's at the back of the engine     Is this the 'chunk' of metal the EGR's housed in?  I haven't cleaned that out yet (but will attempt to on the weekend if there's no difference on it's return).

I cleaned my EGR with some petrol - works a treat (all apart from the thicker bits which I went at with the spoon).   I was dubious of leaving it too long in anything too caustic as the plastic bit the plug would probably have melted... 

So this is something you are now doing on a regular basis?

How often?

Ian.

[TheJoker]

I don't clean it on a regular basis, but having seen the amount of goo in there, I'm expecting that I have to.

[Martin Tyas]

To give another perspective on frequency of EGR removal and cleaning.... my 2.2dCi has covered over 17,000 miles since I last had an episode with a particle of carbon in one of the diaphragms.

Also, there are other factors that can and do come in to play
- driving style
- type of motoring... all local... mostly motorway... or combination
- quality of oil used
- quality of fuel used
- whether just the EGR has been previously cleaned and replaced or the diffuser housing cleaned as well

So just the same as with the extent of performance loss due to an EGR issue as I've previously mentioned, the same applies to frequency..... there isn't a rule book.

Martin

[ianP]

Hi,  as expected,  I picked my car back up from the dealer after they'd sorted out the problems - and it's still the same.   I'm sticking with the assumption that there's still an EGR problem for the moment (as have no idea what else it could be).

I was wondering if it's worth me trying to clean out the EGR valve housing?  The valve itself is now very clean and seems to operate quite smoothly...  I know various people on this forum have had some success with this - and also advocate cleaning this at the same time as the valve,  so thought I should give it a go to rule our the EGR as the cause of my problem (or obviously fix it).

I've started the job of removing the housing but it seems to be quite a big job (bigger than I thought it was going to be)!

What I've done so far is...

• Removed the air filter and housing.
• Removed the 4 bolts from the top of the housing
• slackened off the 2 clips on the hose going into the housing
• I've also removed the EGR valve

Problem is, I can't really take the top off the housing until the hose is removed - but can't do that until the rather large 'plastic thing' above it is removed (I have no idea what this is!)...  there's about 10 bolts in it.  I stopped there to seek some professional advice!

Could anybody send me some instructions of the most efficient way to remove the housing (I think I may be going about it the wrong way)...

Also, I'm not a mechanic (computer programmer actually -  so have really soft hands!) - don't mind getting them dirty however and would be able to follow some instructions on this... but -   please tell me if you think this job should be left to a 'pro'.  I'd hate to take it apart then not be able to put it all back together again (couldn't stand the embarrasement or getting it towed to a garage by a 'proper' mechanic with half the engine missing!) 

Thanks for your assistance.

Ian

[Martin Tyas]

Remove the bottom hose from the diffuser housing and also the steel/cast tube that goes to the block. Then remove the 3 bolts that secure the diffuser housing to the engine block. The diffuser can then be lowered away from the top hose..... but.... as it seems from your description that you have already removed the 4 bolts from the upper section then you can separate the two parts as you lower the diffuser and then remove the upper section from the upper hose.
A cautionary point... the EGR and diffuser are above the starter motor and the positive terminal is exposed so either disconnect the battery or be very careful that you don't drop any of the bolts or tools that could complete a circuit between the terminal and earth (such as the engine block) and give you a surprise 

If you want to know what the diffuser housing should look like without the carbon then here's one I made earlier 

Martin

[Anders Dinsen]

You are showing off, aren't you Martin! Wow...
I think this would look more like what you'd find in the real world

[ianP]

Nice illustration Anders...  being as artistic as you obviously are, how can you be any good at fixing cars? 
 

[ianP]

Hi Martin,  thanks for the reply... I'm not far off then by the look of it.  That does seem to be an easier way than I was imagining.  Good point about the starter motor also... I'll be careful about that (will use a cloth to cover it before I dismantle anything else).

How did you get the diffuser that clean by the way?  looks like a new part.

Will try this out on Friday (I'm off work) - only problem is - I'm driving my family to France on Saturday so if it doesn't all go back together and we miss our ferry,  I'm going to have to blame you     

I'll let you know how I get on.

Cheers,
Ian

[Martin Tyas]

How did you get the diffuser that clean by the way?  looks like a new part.

That's because it is a new part 

The very first time I had a problem that turned out to be the EGR I had called out the AA breakdown service. The second time I sorted it myself but discovered that the AA man must have needed a spare bolt for something else because he'd only put 2 back in!!. Whether he'd cross-threaded it trying to put the bolt back in... it was the least accessible one under the valve.... and then given up I don't know but it's never since felt like it would hold if I tried to really tighten it fully.
The bolts are M6 (6mm threads/10mm hex head) and my plan was to tap it out to M7. Although not very common I did manage to get hold of some M7's (seemingly they are used on Japanese motorbikes!!) but the problem I encountered was with the EGR. The two halves of the EGR (solenoid and valve body) are assembled together using like eyelets.... they rivet the two components together and the mounting bolts go through them. The problem I encountered is that there is insufficient material in the eyelets to stand being opened up enough to accommodate a 1mm larger diameter bolt.
Being tight for time and needing to get the car back on the road quickly on that occasion I decided to order a replacement diffuser (just over £50 at the time) thinking that it would save me time not only with sorting out the problem thread (that would have had to be helicoiled) but also the time to clean it.
However, the replacement diffuser didn't arrive next day so in the meantime I had a rumage through a tub of old nuts and bolts in the garage and found a 9/32" BSF (left over from a 1963 MGB that I'd sold in 1977 but just knew the bits would come in handy some time ) that did the job just fine.
So, the new diffuser has been sat in the garage ever since... the plan being to replace it when I next had an EGR issue.... but it's done 17,000 miles since.

BTW... thanks for getting my hand so dirty with your carbon deposits Anders 
Martin

[Anders Dinsen]

Nice illustration Anders...  being as artistic as you obviously are, how can you be any good at fixing cars? 
 

Haha.... good question!
I'm afraid the answer is - I'M NOT, I just like talking about fixing cars

BTW... thanks for getting my hand so dirty with your carbon deposits Anders

No problem, I'm always at your service

[joejoe]

Hi,
would an obvious answer to all these EGR problems not be to simply disconnect / blank the valve off.

No one can tell me that pumping dirty exhaust gasses into the air intake of any engine is good for it, just look at the crud that is sitting there in the inlet manifold & this will be all over the inlet valves etc....it's just silly.

[Sommerby]

I have now been doing more than 60.000km with my 2.2DCI and had to clean the EGR valve frequently until I decided simply to disconnect it after a cleaning.
Aften then I have been running at least 30.000km without EGR related problems. 
(during the 60.000km I have had 3 back wheel bearings replaced, fuelpump replaced, clutch replaced, 4 glow plugs replaced, but I still love the bugger 
 


Best Regards
Bo

[MarkJHarris]

Hi all.

New to the forum and owner of a 2006 model 2.2Dci. The Diffuser lookes like mine, mine as a solenoid operated EGR valve. Car gives crap fuel consumption and soots under power. Clearly the boost is going somewhere except into the engine as it's not as perky as I'd expected.

It is an Auto box though.....

My biggest problem as it's under warranty still, and the local dealer is not exactly helpful. I took the EGR out and cleaned it up, and the inner valve head is sealing properly, as petrol won't flow through, but the outer one is still 1/2mm open. Where does the air vented out of this go to? if it's going round and back into the engine, then that must be a balance valve to stop boost pressure holding the valve shut, but if it's meant to be sealed properly, can someone tell me please.

They tell me it's fine, but I have previous experience of main dealer mechanics here on the Isle of Man.

[roy4matra]

Hi,
would an obvious answer to all these EGR problems not be to simply disconnect / blank the valve off.

Well, yes, you could disconnect and blank it off, but then the emissions will exceed the limits it was designed for - don't blame the manufacturers entirely here, as they have to design their engines and systems to meet the limits set in Brussels.  And what you are also saying is that 'you couldn't care less about the environmental pollution as long as your vehicle runs fine'.  If everyone takes that attitude, then we will soon be back to pre-emission controlled pollution levels...

No one can tell me that pumping dirty exhaust gasses into the air intake of any engine is good for it, just look at the crud that is sitting there in the inlet manifold & this will be all over the inlet valves etc....it's just silly.

It's got nothing to do with being good for the engine - the manufacturers have to meet the stringent emission levels set by the law makers.  These cover all the various gaseous type pollution as well as particulate emissions.  Very often to meet these rules, the things they have to do are the opposite of what they would do if they just wanted good drive ability, performance, or good fuel consumption.  With EGR, they are re-circulating a small amount of exhaust gas to lower the nitrous oxides if I remember correctly, and yes, it does reduce the power too, because instead of a full cylinder charge of clean air and fuel, some of the space is taken up by the re-circulated exhaust gases.  It's not what they would do given a free hand but they have to meet the regulations otherwise they cannot sell the vehicles.

When they first came out with the particulate traps for diesels that burnt them off periodically (again to meet current legislation), these were fine for cars used on the open roads, but in cities like London they were hopeless.  The car would fail in just 60 miles, since they never ran fast enough or long enough to go through a burn cycle - the instruction was to drive for twenty minutes at no less than 70 kph!  Where in London can you get up to 70 kph (legally) for even a few minutes let alone twenty!!

One of the great problems with lots of todays regulations is that they are often drawn up by people who don't understand the systems, technology, or problems they cause, but they simply write the rules regardless.  It is only years later they come to realise they have created more problems than they have cured...  Leaded fuel was far less a hazard than the low-leaded that we are now forced to use.  It is highly carcinogenic and has higher particulates, whilst the type of lead used (TEL) itself was harmless to humans - it was poison to catalytic convertors which the Americans were insisting on.  I have reams of data on these things which shows how we took the wrong decisions but that is what happens when you let politicians and marketing people rule...

Sorry for the rant, but if you want to disconnect your EGR, go ahead, but it seems we are all wasting our time and money.

Roy

[MarkJHarris]

Roy or anyone,

Can you tell me if that outer valve is meant to be fuly closed and where the gas it does vent goes to please? I'm intrigued, and Diesel is still £1:15.9p where I live!!